Land Use

Peatlands

Harvested peatlands in Ireland as seen from a drone. Peatland ecosystems cover 17 percent of the Irish Republic and have been hand cut— what was known as “working in the moss”—for fuel and winter warmth since Roman times. Today, machines employed by the state- owned company Bord na Móna have replaced people, leaving boglands irreparably damaged. In 2015, the company announced it would phase out all peat cutting by 2030 and make a transition to sustainable biomass, wind, and solar power.

Peatlands, also known as bogs or mires, are neither solid ground nor water but something in between. Peat is a thick, mucky substance made up of dead and decomposing plant matter. It develops over hundreds, even thousands of years, as wetland vegetation slowly decays beneath a living layer of flora and in the near absence of oxygen.

Although these unique ecosystems cover just 3 percent of the earth’s land area, they are second only to oceans in the amount of carbon they store—twice that held by the world’s forests, at an estimated 500 to 600 gigatons. Protecting them through land preservation and fire prevention is a prime opportunity to manage global greenhouse gases.

Because peatlands’ typical carbon content is over 50 percent, they become powerful greenhouse chimneys if disrupted. When peat is exposed to the air, the carbon it contains gets oxidized into carbon dioxide. It can take thousands of years to build up peat, but a matter of only a few to release its greenhouse cache once it is degraded.

Luckily, 85 percent of the world’s peatlands are intact. Though not as effective as halting degradation before it starts, restoring drained and damaged peatlands is an essential complement to protection.

#13

Rank and Results by 2050

21.57 gigatonsreduced CO2

1230.38 gigatonsCO2 protected

Global cost and savings data too variable to be determined

Impact: If the total protected area of peatlands increases from 7.9 million acres to 608 million acres by 2050, or 67 percent of all currently intact peatlands, 21.6 gigatons of carbon dioxide emissions can be avoided. At 608 million acres, peatlands would hold a protected stock of 336 gigatons of carbon, or roughly 1,230 gigtons of carbon dioxide if released into the atmosphere. Though peatlands comprise only 3 percent of global land area, they are the most organic-rich soils; their degradation would release an enormous amount of carbon. Financials are not projected as they are not incurred at the landholder level.

Errata

Technical Summary

Peatlands

Project Drawdown defines peatlands as: the protection of carbon-rich peatlands, leading to reduced degradation rates and the safeguarding of carbon sinks. This solution replaces the destruction of non-degraded peatlands for numerous uses.

Peatlands are a hugely important stock of soil organic carbon. Despite covering only 3 percent of the global land area, they hold 30 percent of all soil carbon, amounting to at least 500 gigatons – twice the carbon stock of all forest biomass. Unlike most terrestrial ecosystems, peatlands do not reach saturation, and continue sequestering carbon in soil organic matter for centuries or millennia.

Peatlands are currently being degraded for agricultural, horticultural, forest, fuel, and infrastructural needs. An estimated 15 percent of the world’s peatlands have been degraded so far, and nearly 50 percent of that degradation is for agricultural land use.

Peatland degradation for various land uses is leading to enormous carbon emissions. Currently, peatlands are degrading at the annual rate of 0.4 million hectares per year. Moreover, global peat volume is decreasing at an annual rate of 20 cubic kilometers per year. Peatland degradation results in nearly 3 gigatons of carbon dioxide-equivalent emissions per year, equivalent to more than 10 percent of global fossil fuel emissions (Biancali and Avagyan, 2014). The rate is expected to increase in the future unless land management practices and peatland development plans are changed and reconsidered.

It is extremely important to prevent any further degradation of peatlands as well as to develop sustainable management plans for already degraded peatlands. The peatlands solution projects adoption of protection of non-degraded peatlands.

Total land allocated for the peatlands solution is 369 million hectares, comprising global peatlands. [2] The total land area available for this solution was modeled using the annual rate of peatland degradation (e.g. from deforestation and mining): 0.52 percent. Future degraded and non-degraded areas were calculated, and the projected future non-degraded, non-protected area was set as the total available area for protection. Current adoption [3] of peatlands is estimated at 3.3 million hectares (Silvius, 2006).

Seven custom adoption scenarios were developed based on commitments such as those of the Irish Peatland Conservation Council (2017), using the linear growth curve. Given the small area of peatland, and the high urgency because of the degradation of unprotected peatland areas and the high mitigation efficiency of protection, several scenarios emphasized early peak adoption by 2030.

Impacts of increased adoption of peatlands from 2020-2050 were generated based on three growth scenarios, which were assessed in comparison to a Reference Scenario where the solution’s market share was fixed at the current levels.

Plausible Scenario: This scenario results in the protection of 246.3 million hectares of unprotected peatlands by 2050.

Drawdown Scenario: This scenario intensifies adoption based on aggressive adoption scenarios, and results in the protection of 341.6 million hectares of peatlands by 2050.

Optimum Scenario: The most aggressive adoption scenario results in the protection of 344.2 million hectares of peatlands by 2050.

Full 100 percent protection of unprotected peatlands was limited by the continuous annual rate of peatland degradation (0.52 percent), even under the most aggressive adoption scenarios.

Emissions and Sequestration Model

Peatland sequestration rates are set at 1.4 tons of carbon per hectare per year, based on 20 data points from 6 sources. Emissions reductions are set at 41.2 tons of carbon dioxide-equivalent per hectare per year, while nitrous oxide reduction is 2.9 tons of carbon dioxide-equivalent per hectare per year. The value for carbon dioxide-equivalent is based on meta-analysis of 104 data points from 32 sources, while nitrous oxide uses 25 data points from 7 sources. Emissions from peat extraction were not modeled.

Financial Model

This study did not model financials, as costs are not necessarily carried out by the landowner or land manager.

Drawdown’s Agro-Ecological Zone model allocates current and projected adoption of solutions to the planet’s forest, grassland, rainfed cropland, and irrigated cropland areas. This study assumes that all peatland is on forested land. Peatland protection is the top priority for forested land.

Results

Total adoption of peatlands in the Plausible Scenario is 246.3 million hectares in 2050, representing 66.7 percent of the total suitable land. Of this, 243 million hectares are adopted from 2020-2050. The emissions impact of this scenario is 21.6 gigatons carbon dioxide-equivalent by 2050. Total carbon protected is 335.8 gigatons carbon dioxide-equivalent. Financial impacts are not modeled.

Total adoption in the Drawdown Scenario is 341.6 million hectares in 2050, representing 92.5 percent of the total suitable land. Of this, 338.3 million hectares are adopted from 2020-2050. The impact of this scenario is 33.5 gigatons carbon dioxide-equivalent by 2050. Total carbon protected is 465.8 gigatons carbon dioxide-equivalent.

Total adoption in the Optimum Scenario is 344.2 million hectares in 2050, representing 93.2 percent of the total suitable land. Of this, 344.2 million hectares are adopted from 2020-2050. The impact of this scenario is 36.6 gigatons carbon dioxide-equivalent by 2050. Total carbon protected is 469.4 gigatons carbon dioxide-equivalent.

Discussion

Benchmarks

Annual emissions from degraded peatlands today are estimated at 1.0 gigatons carbon dioxide-equivalent per year (IPCC, 2014). This will surely increase as degradation is ongoing. The Drawdown model calculates emissions reduction of 1.3, 1.9, and 2.0 gigatons carbon dioxide-equivalent per year by 2050 in the Plausible, Drawdown, and Optimum Scenarios, respectively. This study is within range of this benchmark, as the degraded area will continue to grow in business-as-usual scenarios, and emissions will continue from degraded peatlands for decades or longer given the immense size of the stocks.

Limitations

It would be useful to project peatland restoration as well as protection. Projecting financials at the government or non-governmental organization level is also recommended.

Conclusions

The extremely high carbon stocks of peatlands, combined with their relatively tiny global extent, indicate that their protection should be an extremely high priority for climate mitigation.

[1] To learn more about the Total Land Area for the Land Use Sector, click the Sector Summary: Land Use link below.

[2] Determining the total available land for a solution is a two-part process. The technical potential is based on the suitability of climate, soils, and slopes, and on degraded or non-degraded status. In the second stage, land is allocated using the Drawdown Agro-Ecological Zone model, based on priorities for each class of land. The total land allocated for each solution is capped at the solution’s maximum adoption in the Optimum Scenario. Thus, in most cases the total available land is less than the technical potential.

[3] Current adoption is defined as the amount of functional demand supplied by the solution in the base year of study. This study uses 2014 as the base year due to the availability of global adoption data for all Project Drawdown solutions evaluated.

[4] To learn more about Project Drawdown’s three growth scenarios, click the Scenarios link below. For information on Land Use Sector-specific scenarios, click the Sector Summary: Land Use link.

[5] For more on Project Drawdown’s Land Use integration model, click the Sector Summary: Land Use link below.